The work deals with the development of phenomenological law of soil ma
ss transport by surface water flow. Well-known in mechanics as the pi-
theorem, the equation of mass conservation of a mix on the phase bound
ary (water-soil) and assumption about similarity of field of particle
concentrations in a flow to the field of velocities were assigned as t
he basis of development. A new equation of soil loss was obtained. The
arguments of this equation are: shear stress of flow, average flow ve
locity and scouring velocity. Empirical coefficients were found on the
basis of the laboratory experimental research of relation between the
removal intensity of some pre-mountain soils of the southeastern slop
e of Large Caucasus and the velocity of flow. (C) 1998 Elsevier Scienc
e B.V. All rights reserved.